Nutritional Therapy

Nutrition is one of the most challenging and important issues
for women with HG. Pregnant women require a variety of nutrients
both for their own healing and for the normal development
of their unborn child. The baby's requirements for minerals,
vitamins, and other nutrients come first and are taken from
the mother's bones, organs, tissues, and other storage areas.
This can leave the mother depleted very quickly, which can
take months, or even years, to correct.

These nutrients are also needed to form the placenta, to
increase the size of the uterus and breast tissue, and to
create amniotic fluid. A mother's blood volume increases by
25–50%, and more fluids, iron, B12, folic acid, zinc
and copper, calcium, magnesium, and proteins are needed to
support this new blood. Storage levels of most nutrients must
be obtained from the diet as well. A nutritional consult may
be helpful both during and after pregnancy to ensure she sufficiently
rebuilds her nutrient stores, especially before becoming pregnant
again.

Food Aversions and Cravings

It is very typical for mothers with HG to have very strong
cravings and aversions that prohibit a well-balanced diet
for much of their pregnancies, and these preferences may change
frequently until delivery. It may be the smell, texture, appearance
or taste that leads to nausea and vomiting.

The cause is likely a complex interaction of endocrine (hormone)
changes related to pregnancy, nutrient deficiencies, mechanical
changes in the body, gastrointestinal dysfunction (e.g. reflux),
and changes in neurochemicals. The intensity of cravings and
aversions can be very high and trigger repeated bouts of severe
nausea and/or vomiting.

Thinking about foods, smelling them, or even just seeing
food on the television is enough to trigger vomiting for many.
She may crave very specific combinations of food characteristics,
such as salty and crunchy, or sweet and soft. Entering a grocery
store, opening the refrigerator, or even contemplating food
preparation are usually intolerable for at least the first
trimester. This has significant impact both on her and her
family, and is not something she can control.

These issues have to be acknowledged, supported and accepted
by her family and care providers. It's impossible to fully
understand the unusual dietary preferences of HG unless you
have experienced it for yourself. Trying to force other foods
that do not appeal will typically result in vomiting and greater
anxiety for the mother.

Nutritional Deficiencies and Hyperemesis

Women with HG may vomit or have severe nausea for months
that will leave her exhausted and very depleted. It is imperative
that women losing weight rapidly and not responding to medications
be given nutritional support. Research has shown significant
nutrient depletion in these women. Vitamins, especially B-vitamins,
are depleted very quickly and if not replaced can worsen her
symptoms or put her at risk for life-threatening neurological
disorders like Wernicke's
Encephalopathy.

At a minimum, mothers requiring hydration should also receive
vitamins and electrolytes. Those who continue to lose over
5% of their body weight in the early months should be considered
for IV nutrition to protect the mother and child's well-being.
Studies show that an inadequately nourished fetus may grow
and develop more slowly, have chronic
disease in later life,
and is more likely to be preterm.

These mother's are also at greater risk for complications
such as pre-eclampsia and postpartum depression. Ironically,
nutrition is likely the most prolific topic related to pregnancy,
yet when a woman has HG, she is often told malnutrition will
not harm her unborn child or herself. Surgical patients are
given nutritional therapy typically within one week if they
are still unable to eat. However, it is ironic that mothers
with HG may go weeks or months nearly starving and not receive
nutritional support. The research does not support the idea
that prolonged starvation is acceptable during pregnancy.
These women should be given interventions and better care
to promote a healthier outcome for both the mother and child.

Mean dietary intake of most nutrients fell below 50% of the recommended dietary allowances and differed significantly (p < 0.01) from that of controls. More than 60% of the patients had suboptimal biochemical status of thiamine, riboflavin, vitamin B6, vitamin A, and retinol-binding protein. Vitamin C, calcium, albumin, hematocrit, and hemoglobin values were significantly higher in those patients where the duration of vomiting had been longer, suggesting the presence of dehydration. Treatment was associated with cessation of vomiting and improvement in blood nutrient status. Pregnancy outcome was favorable in all patients. The hyperemetic pregnant patient is at nutritional risk; prompt initiation of corrective therapy is recommended.

Mean dietary intake of most nutrients fell below 50% of the recommended dietary allowances and differed significantly (p < 0.01) from that of controls. More than 60% of the patients had suboptimal biochemical status of thiamine, riboflavin, vitamin B6, vitamin A, and retinol-binding protein. Vitamin C, calcium, albumin, hematocrit, and hemoglobin values were significantly higher in those patients where the duration of vomiting had been longer, suggesting the presence of dehydration. Treatment was associated with cessation of vomiting and improvement in blood nutrient status. Pregnancy outcome was favorable in all patients. The hyperemetic pregnant patient is at nutritional risk; prompt initiation of corrective therapy is recommended.

Recurrent hyperemesis gravidarum is a frustrating and poorly studied complication of early pregnancy. Despite published reports that hyperemesis gravidarum has no impact on ultimate perinatal outcome, this study indicated that women admitted repeatedly have a more severe nutritional disturbance, associated with significantly reduced maternal weight gain and neonatal birth weight. These risks argue for more aggressive antenatal treatment and increased fetal surveillance in pregnancies complicated by recurrent hyperemesis gravidarum.